GB2193452A

GB2193452A - Multi-mandrel lathe with lubrication and cooling circuits

Info

Publication number: GB2193452A
Application number: GB08717740A
Authority: GB
Inventors: Enrico Ronzoni
Original assignee: Gildemeister Italiana SpA
Current assignee: Gildemeister Italiana SpA
Priority date: 1986-08-01
Filing date: 1987-07-27
Publication date: 1988-02-10
Anticipated expiration: 2007-07-27
Also published as: IT8621362A1; DE3724599A1; GB2193452B; DE3724599C2; CH671722A5; GB8717740D0; IT8621362A0; IT1197041B

Description

GB2193452A 1 SPECIFICATION the recovery of said coolant fluid, provided

with a tank, a pump and heat exchanger, con Multi-mandrel lathe with lubrication and nected in sries to one another.

cooling circuits For the purpose of better understanding the 70 characteristics, and further advantages of the The object of the present invention is a multi present invention, said invention is disclosed mandrel lathe with lubrication and cooling cir- now by referring to the hereto attached draw cuits. ing tables, wherein:

Multi-mandrel lathes are known, wherein the Figure 1 shows a longitudinal sectional view lubrication is obtained by different lubrication 75 of a lathe according to the present invention; systems, of oil bath lubrication, or oil feeding Figure 2 is a transversal sectional view of lubrication types, which generally require a the lathe of Fig. 1; and considerable amount of lost oil (loss lubrica- Figure 3 is a schematic perspective view of tion). an element of Fig. 1.

Furthermore, such lubrication systems are 80 Referring to the Figures, with 10 a lathe sometimes insufficient for the moving mem- according to the present invention is generally bers, causing them to wear out, with the con- indicated, wherein a casing 11, inside which a sequent additional costs. drum 12 is housed, is substantially visible.

Another drawback which is shown by the The drum 12 is constituted by cylindrical multi-mandrel lathes is due to the tempera- 85 flanges 13 and 14 between which a plurality tures which are reached during the machining, of tubular members 15, circumferentially in the drum-and in such therein housed mem- placed on flanges 13 and 14, are housed; bers, as rolling bearings and mandrels. Such centrally, still between said flanges, a further temperatures, which are rather high, cause the tubular element 16 is provided.

seats to expand, becoming ovalized, with the 90 Inside each one of the tubular elements 15, consequent occurrence of expansions and a mandrel (not shown) is housed, whilst inside shifts of the mandrels and their axes. From the further tubular element 16, a central tube the above, a surely not very high machining 17 is housed, which is integral with said tubu precision derives, with tolerances which some- lar element 16, and hence with the drum 12.

times are unacceptable. 95 In a coaxially inner position inside the cen A purpose of the present invention is to tral tube 17, a central shaft 18 is provided, provide a multi-mandrel lathe which has an which can rotate independently from the cen efficient lubrication circuit for each running tral tube 17 and from the drum 12. Between member, and which allows, at the same time, the central shaft 18 and the central tube, an certain amounts of lost oil to be saved. 100 air gap 19 is provided, inside which a first Another purpose of the present invention is lubrication pipe 21, integral with the central to provide a lathe with a drum which has an tube, runs.

essentially thermosymmetrical structure, The lubrication pipe 21 is fed by a rotary capable to be cooled by a special fluid circula- coupling 22 provided at an end 23 of the tion loop. 105 central pipe in an opposite position relatively In view of such purposes, according to the to the tube portion housed inside the drum present invention a multi-mandrel lathe with 12.

lubrication and cooling circuits has been pro- The first pipe 21 is connected with a sec vided, of the type essentially constituted by a ond pipe 20, internal to the drum 12, and drum, rotatably mounted on a central shaft 110 essentially positioned in a radial arrangement; and integral with a central tube, said central the second pipe 20 is connected with a first tube being coaxially'external to said central oil distributor 23 installed on one of the tubu shaft and said drum being furthermore rotatalar elements 15.

bly housed inside a casing, characterized in The first distributor 23 is connected in that between said central tube and said cen- 115 series with second distributors 24, provided tral shaft, independent from each other, an air on the tubular elements 15 in the nearby of gap is provided for the passage of a feeding each flange 13 and 14, by means of further line of a lubrication circuit for said drum, said pipes 25.

line being, fed by means of a rotary coupling Each one of the oil distributors is of the provided at one of its ends, said circuit being 120 drip-feed type and is connected with the in- constituted by a plurality of metering units side of said tubular elements 15 for the pur connected in series and connected with said pose of lubricating with pre- established oil drum for lubricating the mandrels of said lathe, amounts the running members of said man said casing being equipped with means for drels.

cooling said drum. 125 Furthermore, still according to the present Advantageously, still according to the pre- invention, a fluidcirculation and fluid-recovery sent invention, said casing, inside which said cooling circuit iS' provided, which is indepen drum is housed, is provided with an inlet port, dent and separate from the hereinabove dis and a discharge port, for an independent cir- closed lubrication circuit.

cuit for the fluid cooling of said drum, and for 130 Such circuit comprises a feeding tank, sche- 2 GB2193452A 2 matically indicated in 26, from which a fluid port and with a discharge port for a cooling 27 is drawn by means of a pump 28. The circuit for fluid-cooling said drum.

pump 28 delivers the fluid 27, through a heat 3. Multi-mandrel lathe according to claims exchanger 29, up to an inlet pipe 30. 1 and 2, characterized in that said cooling The pipe 30 enters the casing through a 70 circuit is a falling-coolant circuit.

port 31, and extends into the upper portion 4. Multi-mandrel lathe according to claims thereof. 1 and 2, characterized in that said cooling The stream of falling fluid 27 impinges thus circuit is independent, and is a fluid-recovery against the drum 12, and is recovered in the circuit.

bottom portion of the casing through a pipe 75 5. Multi-mandrel lathe according to claims 32 connected with the tank 26. 1 and 2, characterized in that said cooling The particular shape of the drum 12 allows circuit is provided with a tank, a pump and a the cooling fluid 27 to cool it in a nearly sym- heat exchanger connected in series with one metrical way, and furthermore the circuit, another, said tank being connected with the completely separated from the working areas, 80 bottom portion of said casing, and said heat wherein turnings and, generally, impurities, are exchanger being connected with an inlet pipe produced, makes it possible the cooling fluid entering the upper portion of said casing.

to be recovered without any wastes. 6. Multi-mandrel lathe according to claims The basic advantage which is yielded by the 1 and 2, characterized in that said cooling present cooling circuit consists mainly in a lesfluid is oil.

ser thermal expansion of the hot portions and 7. Multi-mandrel lathe according to claim 1, of the running parts, and, consequently, better characterized in that said drum is constituted precisions are obtained in the several machin- by, cylindrical flanges between which a plurality ings. of tubular elements are housed, said tubular Advantageously, the fluid used for the cool- 90 elements being placed in a circumferential ar ing, according to a form of practical embodi- rangement on said flanges, and moreover a ment of the present invention, is oil. further central tubular element being provided A further advantage of cheapness and effick for the housing of said central tubular element.

ency is moreover given by the lubrication cir- 8. Multi-mandrel lathe according to claim 1, cuit which, by being provided with metering 95 characterized in that said drum has a thermo units, delivers oil drops according to pre- symmetrical structure.

established times and amounts, in any case 9. Multi-mandrel lathe according to claim 1, sufficient for an optimum lubrication, but characterized in that on said tubular elements which, at the same time, allows considerable belonging to said plurality a metering unit is amounts of this oil, which gets lost, to be 100 provided in the nearby of each one of said saved. flanges.

The present invention has been disclosed 10. Multi-mandrel lathe according to claim for illustrative and non-limitative purposes, and 1, characterized in that each one of said met it must be understood that changes and varia- ering units is of the drip- feed type.

tions can be supplied by those skilled in the Published 1988 at The Patent Office, State House, 66/71 High Holborn, art, without anyway leaving the scope of pro- London WC 1 R 4TP. Further copies may be obtained from tection of the present patent-right. The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD.

Printed by Burgess & Son (Abingdon) Ltd. Con. 1/87.

Claims

1. Multi-mandrel lathe with lubrication and cooling circuits, of the type essentially consti tuted by a drum, rotatably mounted on a cen tral shaft and integral with a central tube, said central tube being coaxially external to said central shaft and said drum being furthermore rotatably housed inside a casing, characterized in that between said central tube and said central shaft, indepqndent from each other, an air gap is provided for the passage of a feed- ing line of a lubrication circuit for said drum, said line being fed by means of a rotary coupling provided at one of its -ends, said circuit being constituted by a plurality of metering units connected in series and connected with said drum for lubricating the mandrels of said lathe, said casing being equipped with means for cooling said drum.

2. Multi-mandrel lathe according to claim 1, characterized in that said casing -inside which said drum is housed is provided with an inlet